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Sildenafil

Mar 14, 2016
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Sildenafil's vasodilating effects are known to enhance sporting performance, bringing more blood to the lungs and thereby improving oxygenation. Cycling is the number 1 consumer of sildenafil in sports. Yet this drug is not on the WADA list of banned products. Why?
 
May 6, 2016
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Sildenafil: https://www.drugs.com/cdi/sildenafil.html

Sildenafil is used for:

Treating high blood pressure in the lungs (pulmonary arterial hypertension [PAH]). It may also be used for other conditions as determined by your doctor.

Sildenafil is a phosphodiesterase type 5 (PDE5) inhibitor. It works by relaxing and dilating the blood vessels in the lungs. This lowers the blood pressure in the lungs and helps to improve your ability to exercise.
 
CheckMyPecs said:
Yet this drug is not on the WADA list of banned products. Why?
Have you checked that? I mean, actually checked that, not just done a Ctrl+F on the banned list but looked to the catch-all rules (eg M1) and clarified the matter directly with WADA?
 
I thought all the studies on it were pretty inconclusive regarding highly trained athletes. As in, "it might work for some people, at a certain level of fitness, in certain conditions" kind of thing - rather than a clear univesal performance enhancer.
 
Mar 14, 2016
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Re:

Red Rick said:
Sounds interesting. Do you have sources?
Yes.

That’s essentially what the study that created the initial splash concluded, though those findings got lost in the dust-up from the resulting media stampede. To recap: In a study published in the June 2006 issue of the Journal of Applied Physiology, researchers had 10 trained cyclists perform a series of time trials at sea level and then at high altitude (12,700 feet) while taking Viagra and placebo pills (obviously never knowing which was which). On average, Viagra improved performance by a whopping 15 perecent—but mostly because four of the guys really responded, increasing the amount of blood pumped by their hearts by 32 percent during the TT, and improving their overall performance by an astonishing 39 percent. The rest saw zero improvement, or even got worse. One (the study originally had 11 volunteers) had to quit the study midstream because he couldn’t hack the wicked Viagra headaches (more on that in a moment). None improved at sea level.

http://www.bicycling.com/training/health-injuries/viagra-different-kind-performance-enhancement
Basically, if you're a non-responder there's no use for sildenafil, but if you're a responder, you'll reap huge benefits.
 
Re: Re:

CheckMyPecs said:
Red Rick said:
Sounds interesting. Do you have sources?
Yes.

That’s essentially what the study that created the initial splash concluded, though those findings got lost in the dust-up from the resulting media stampede. To recap: In a study published in the June 2006 issue of the Journal of Applied Physiology, researchers had 10 trained cyclists perform a series of time trials at sea level and then at high altitude (12,700 feet) while taking Viagra and placebo pills (obviously never knowing which was which). On average, Viagra improved performance by a whopping 15 perecent—but mostly because four of the guys really responded, increasing the amount of blood pumped by their hearts by 32 percent during the TT, and improving their overall performance by an astonishing 39 percent. The rest saw zero improvement, or even got worse. One (the study originally had 11 volunteers) had to quit the study midstream because he couldn’t hack the wicked Viagra headaches (more on that in a moment). None improved at sea level.

http://www.bicycling.com/training/health-injuries/viagra-different-kind-performance-enhancement
Basically, if you're a non-responder there's no use for sildenafil, but if you're a responder, you'll reap huge benefits.
Are there any studies on how well trained these four guys were? And what their improvement was? If they improved TT performance by 39%, then I'm guessing they were starting from a very poor level.
 
Re: Re:

CheckMyPecs said:
DFA123 said:
Are there any studies on how well trained these four guys were? And what their improvement was? If they improved TT performance by 39%, then I'm guessing they were starting from a very poor level.
http://jap.physiology.org/content/100/6/2031.long
Thanks for that. An interesting read - but it looks a bit of a flawed study. Look at Fig 2 for example:

Are they basing the 39% impovement claims against the placebo for the 'responders'? But the placebo was ridiculously slow - 15 minutes for 6km. That's 24km/h. For a 6km TT that's a completely untrained level. The responders actually put in a very similar time to the non responders on average which was still only around 33km/h - again a really, really slow pace for 6km TT.

So they basically took a really small sample of close to untrained cyclists, and those who took sildenafil were able to complete a 6km TT at an average 33km/h, with considerable individual variation - at high altitude.

Looking at a sample size of 11 untrained athletes, responding at high altitude, doesn't really provide any worthwhile data for how it may affect pro cyclists.
 
Re: Re:

DFA123 said:
So they basically took a really small sample of close to untrained cyclists, and those who took sildenafil were able to complete a 6km TT at an average 33km/h, with considerable individual variation - at high altitude.

Looking at a sample size of 11 untrained athletes, responding at high altitude, doesn't really provide any worthwhile data for how it may affect pro cyclists.
it doesn't say much about the TT except that it was on a stationary bike. It could have been set to simulate an uphill TT, no? Further up in the paper it says the subjects had average vo2maxes of around 60 which is a good bit better than "untrained".
 
Re: Re:

proffate said:
DFA123 said:
So they basically took a really small sample of close to untrained cyclists, and those who took sildenafil were able to complete a 6km TT at an average 33km/h, with considerable individual variation - at high altitude.

Looking at a sample size of 11 untrained athletes, responding at high altitude, doesn't really provide any worthwhile data for how it may affect pro cyclists.
it doesn't say much about the TT except that it was on a stationary bike. It could have been set to simulate an uphill TT, no? Further up in the paper it says the subjects had average vo2maxes of around 60 which is a good bit better than "untrained".
This is part of the problem. In such a small sample size, the average is close to meaningless. One guy could have 40 and another two 70. Whatever the numbers are, the fact that the time of the control group of those who took Sildenafil placebo is so much slower than every other group in the test - makes it ridiculous to use that figure to draw conclusions from.

Horrible study, horribly executed I'm afraid.
 

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